Battery light intermittent Fabia 2003 1.4 MPI

[Kiyonari]

Hi,

 

I have a problem with my 2003 1.4 MPI Fabia whereby the battery light comes on intermittently with a beep.  Changed the battery to no avail, and the alternator is putting out over 14v on idle.  Did some reading on here regarding a DFM wire?  Had a look for this this morning and found a purple/green wire which is snapped clean in half, on a plug just infront of the gearbox on a metal bracket (see pictures), could this be the cause of my problem?  Not had chance to fix but will running it in the meantime in this state cause any problems?

 

Cheers!!!

 

 

[Kiyonari]

[KenONeill]

@Kiyonari - Does the battery light come on when you first switch the ignition to position 2? If not, then you pretty much definitely have a broken load sense wire, which may or may not be the one you describe.

[Kiyonari]

@KenONeill - the battery light does come on with the ignition on, then goes off once the engine is started.

 

[KenONeill]

@Kiyonari Well, that definitely rules out the first thought, the load sense wires. I've seen a similar issue caused by a one-way clutch on the alternator not always engaging, so it's worth checking that the alternator commutator is turning over correctly.

[Breezy_Pete]

It is exactly the load sense/DFM wire that's busted. Shouldn't cause any problems driving it 'til you get a chance to repair it.

It's the blue wire that affects the battery light at ignition on.

[Kiyonari]

I'm gunna have a go at repairing it tonight and will let you know what happens.  Is it possible to bypass the plug and just join the two pieces of wire together, as there is only about 1cm of purple wire sticking out of the plug so crimping might be a bit tricky.

 

[Breezy_Pete]

Yep, that's the easiest fix.

[Kiyonari]

Just attempted the fix by chopping the plugs out and connecting the wires, unfortunately still getting the same problem, though it now seems to be more predictable in the battery light comes on when the car is revved and the throttle is released, as the revs settle the battery light comes on an beeps then goes off.  My fix wasnt the best as I have literally just wrapped the wires together and stuck gaffer tape around them so when I get more time I'll try and crimp em together properly.  Must be a wiring fault as don't get any other symptoms 

[Breezy_Pete]

I was afraid that might not fix it. Not sure how much the DFM signal is used on the petrol engines. I once disconnected mine for a week, and noticed no change at all.

Can you post an end-on photo of your alternator pulley (to see whether or not it's the type with clutch/ratchet, as Ken mentions above)?

[Kiyonari]

Sure I'll try get this ASAP thank you